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B1405




DTC B1405

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.

DTC Descriptor
DTC B1405
- Device Voltage Reference Output 2 Circuit

Diagnostic Fault Information





Circuit/System Description

The battery current sensor is a 3-wire hall effect current sensor. The battery current sensor monitors the battery current. It directly inputs to the body control module (BCM). It creates a 5-volt pulse width modulation (PWM) signal of 128 Hz with a duty cycle of 0-100 percent. Normal duty cycle is between 5-95 percent. Between 0-5 percent and 95-100 percent are for diagnostic purposes.

Conditions for Running the DTC

* The ignition is ON.
* The engine is running.

Conditions for Setting the DTC

The BCM detects a duty cycle of PWM input signal is less than 4 percent or more than 96 percent for more 33 seconds.

Action Taken When the DTC Sets

The DTC sets as current , no driver indication or message is displayed.

Conditions for Clearing the DTC

The DTC clears as current status when the battery sensed current returns to normal range for more than 5 seconds.

Reference Information
Schematic Reference

Starting and Charging Schematics ([1][2]Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Charging System Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Testing

B1405
1. Ignition OFF, disconnect the harness connector at the battery current sensor.
2. Ignition OFF, test for less than 5.0 ohms between the low reference circuit terminal B and ground.

If greater than specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the BCM.

3. Ignition ON, test for 4.8-5.2 volts between the battery current sensor supply voltage circuit terminal A and ground.

If less than the specified range , test the battery current sensor supply voltage circuit for a short to ground or an open/high resistance. If the circuit test normal, replace the BCM.

If greater than the specified range , test the battery current sensor supply voltage circuit for a short to voltage. If the circuit tests normal, replace the BCM.

4. Ignition ON, test for 4.8-5.2 volts between the battery current sensor signal circuit terminal C and ground.

If less than the specified range, test the battery current sensor signal circuit for a short to ground or an open/high resistance. If the circuit test normal, replace the BCM.

If greater than the specified range, test the battery current sensor signal circuit for a short to voltage. If the circuit tests normal, replace the BCM.

5. If all circuits test normal, replace the battery current sensor.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Battery Current Sensor Replacement (RPOs LZE/LZ4/LZ8) (Service and Repair)Battery Current Sensor Replacement (RPO LS4) (Service and Repair)
* Control Module References (Programming and Relearning) for BCM replacement, setup, and programming